The present invention relates to a treatment instrument driving device for altering the direction of a treatment instrument, e.g., forceps to be guided to a body cavity through the channel of an endoscope.
The endoscope has been used not only for observation or the photographing of the interior of a body cavity from the exterior, but also for the collection of the pathological tissue in the body cavity by forceps or the therapy of the tissue with a simple operation implement. For that purpose, a treatment instrument driving device for moving forceps or an operation implement to be guided into a body cavity through the channel of an endoscope to an objective position has become an important factor in the endoscope.
According to a conventional treatment instrument driving device, a driving member is arranged in a distal closet provided at the distal portion of an endoscope, being pivotally secured at its one end to the distal portion, and engaged at its other end to an operation wire inserted into the guide tube of the endoscope. The driving member thus rises when the operation wire is pulled, and forceps are then moved to a predetermined position according to the rising angle of the operation wire. With such a structure, a gap is produced between the operation wire and the guide tube, and the gap is exposed with the distal closet. Therefore, a contaminated solid or liquid is feasibly introduced into the gap. The contaminated solid or liquid thus accumulated in the gap not only prevents the rising of the driving member due to the operation wire, but is also unsanitary. Further, the treatment instrument driving device is used in the very narrow position of the endoscope. Accordingly, a problem occurs in the cleaning treatment of the narrow position after use.